BDNF 196 G/A and 270 C/T polymorphisms and susceptibility to parkinson's disease: A meta-analysis

The aim of this study was to explore whether brain-derived neurotrophic factor (BDNF) polymorphisms 196 G/A and 270 C/T confer susceptibility to Parkinson's disease (PD). The authors conducted a meta-analysis of the associations between the BDNF 196 G/A and 270 C/T polymorphisms and PD in subjects. They considered 12 studies in the case of the BDNF 196 G/A polymorphism and 4 studies in the case of the BDNF 270 C/T polymorphism. Meta-analysis showed no association between PD and the BDNF 196A allele in all study subjects (odds ratio [OR] = 1.066, 95% CI [0.972, 1.169], p =.173). However, ethnicity-specific meta-analysis identified an association between the BDNF 196 AA + AG genotype and PD in Europeans, but not in Asians (OR = 1.212, 95% CI [1.007, 1.458], p =.042; OR = 1.0567, 95% CI [0.913, 1.221], p =.465). Meta-analysis showed no association between PD and the BDNF 270 C/T polymorphism (OR for the T allele = 1.213, 95% CI [0.923, 1.595], p =.165). This meta-analysis identified an association between the BDNF 196 G/A polymorphism in Europeans, but not in Asians, but failed to identify an association between the BDNF 270 C/T polymorphism and PD.